contact dermatitis: common culprits · pityriasis alba anterior neck folds itch when sweating...
TRANSCRIPT
Eczema/Dermatitis
Conundrum
• Contact Dermatitis – Clues to Cures
• Atopic Eczema – Dousing the Fire
Leigh Ann Carter, M.D.
MINI-SYMPOSIUM
Contact Dermatitis:
Clues to Cure
Leigh Ann Carter, MD
What Is Allergic Contact
Dermatitis?
Most people are very familiar with Allergic
Contact Dermatitis (ACD) although they may
not realize it….
Common Culprits?
The itchy skin rash caused by exposure to
poison ivy is a classic example of ACD.
Note the
LINEAR
appearance of
the lesions…
This must be
an “outside
job!”
Straight-forward Examples
Another example of ACD is nickel allergy in
someone who reacts to costume jewelry or the
metal button on their jeans.
Nature Clinical Practice Rheumatology (2007) 3, 240-245; Malar rash caused by metal allergy
in a patient with systemic lupus erythematosus, Meghavi Kosboth, et al
Elusive etiologies
Unfortunately all cases of ACD are not
this clear-cut.
There are numerous substances, called
“allergens,” that can cause dermatitis in
sensitized individuals.
Many of these allergens are difficult to
identify.
Elusive etiologies
For example, a patient may be allergic to
various preservatives or fragrances in their
personal care products.
Patients may even be allergic to ingredients in
the medications they are using to treat their
rash. (Initial improvement, but will flare in a
few days.)
Detective work…
In cases such as these, patch testing is used to identify the specific allergens.
Patch testing is a safe and painless process.
Small amounts of suspected allergens are placed onto tape and then applied to the patient’s back.
Patch Testing
Unlike “scratch” or “injection” testing, there
are no needles involved.
The tape is removed after two days and a
reading is made to check for reactions (a red
spot at the location of a particular allergen.)
A final reading is made several days later.
Likely Suspects…
Common allergens include:
metals,
fragrances,
topical antibiotics,
preservatives.
Likely Suspects…
The top 10 allergens recently identified by the
Mayo Clinic Contact Dermatitis Group
(MCCDG) were: Nickel, Balsam of Peru,
Gold, Neomycin, Fragrance mix, Thimerosal,
Cobalt, Formaldehyde, Benzalkonium
chloride, and Bacitracin.
Common Culprits
*Nickel (nickel sulfate hexahydrate) — metal frequently encountered in jewelry and clasps or buttons on clothing
*Gold (gold sodium thiosulfate) — precious metal often found in jewelry
*Balsam of Peru (myroxylon pereirae) — a fragrance used in perfumes and skin lotions, derived from tree resin
*Thimerosal — a mercury compound used in local antiseptics and in vaccines
*Neomycin sulfate — a topical antibiotic common in first aid creams and ointments, also found occasionally in cosmetics, deodorant, soap and pet food
Common Culprits
*Fragrance mix — a group of the eight most common fragrance allergens found in foods, cosmetic products, insecticides, antiseptics, soaps, perfumes and dental products
*Formaldehyde — a preservative with multiple uses, e.g., in paper products, paints, medications, household cleaners, cosmetic products and fabric finishes
*Cobalt chloride — metal found in medical products; hair dye; antiperspirant; objects plated in metal such as snaps, buttons or tools; and in cobalt blue pigment
*Bacitracin — a topical antibiotic
*Quaternium 15 — preservative found in cosmetic products such as self-tanners, shampoo, nail polish and sunscreen or in industrial products such as polishes, paints and waxes
Culprit?
Prior Biopsy Site
Eczematous “weepy” papules
Allergic contact dermatitis can be very
frustrating for patients when they do not know
what is causing their rash.
But with patch testing, the offending allergens
can be identified and successfully avoided.
Case Study
A woman presented with a 6 month history of
dermatitis on her neck and chest.
She denied new exposures during this time
period.
Topical steroids helped, but the eruption
always recurred.
Case Study
Patch testing reaveled a 2+ reaction to Lyral
(The Allergen)
On review of her products, the perfume she
had been using for several years,
Glow by JLo listed hydroxyisohexyl 3-
cyclohexene carboxaldehyde as an ingredient ,
which was noted to be synonymous with
Lyral.
Case Study
The patient had been applying this perfume to her anterior neck on a nearly daily basis for the past several years.
This is a case where more extensive patch testing was needed. Lyral is not included in the routine screening allergens for fragrances.
Allergies can develop at any time. The longer a patient has been exposed to something, the more likely they are to become sensitized to it.
Pearls
Poison Ivy is a classic example of Allergic Contact Dermatitis.
Look for a LINEAR arrangement of lesions as a clue to an “outside” etiology. This is most common with plants.
Common allergens include: metals,
fragrances,
topical antibiotics,
and preservatives.
Bactroban (mupirocin) ointment is a good alternative to Neosporin (triple antibiotic) ointment if you suspect contact dermatitis but do not wish to patch test yet.
Patients may even be allergic to ingredients in the medications they are using to treat their rash. (Initial improvement, but will flare in a few days.)
Patch testing is not the same as scratch testing.
Allergies can develop at any time.
The longer a patient has been exposed to something, the more likely they are to become sensitized to it.
Eczema:"to boil out"
Eczema: "to boil out"Weepy, oozing, wet lesions…
Edema fluid escapes
through the epidermis. This is called "spongiosis" by
pathologists. Think of the
epidermis as a sponge filled
with fluid.
Distribution
Adolescence and Adulthood
From Fitzpatrick TB, et al. Color Atlas and Synopsis of Clinical Dermatology. 2nd ed. New York, NY: McGraw-Hill, Inc;1991: 27.
Hanifin and Rajka Diagnostic Criteria for Atopic
Dermatitis (AD)
Major criteria: Must have three or more of:
Pruritus
Typical morphology and distribution
Flexural lichenification or linearity in adults
Facial and extensor involvement in infants and
children
Chronic or chronically-relapsing dermatitis
Personal or family history of atopy (asthma, allergic
rhinitis, atopic dermatitis)
Minor criteria: Should have three or more of:
Xerosis
Ichthyosis, palmar hyperlinearity, or keratosis pilaris
Immediate (type 1) skin-test reactivity
Raised serum IgE
Early age of onset
Tendency toward cutaneous infections (especially S
aureus and herpes simplex) or impaired cell-mediated
immunity
Tendency toward non-specific hand or foot dermatitis
Nipple eczema
Cheilitis
Recurrent conjunctivitis
Minor criteria, cont.:
Dennie-Morgan infraorbital fold
Keratoconus
Anterior subcapsular cataracts
Orbital darkening
Facial pallor or facial erythema
Pityriasis alba
Anterior neck folds
Itch when sweating
Intolerance to wool and lipid solvents
Perifollicular accentuation
Food intolerance
Course influenced by environmental or emotional
factors
White dermographism or delayed blanch
D. Exclusions: Firm diagnosis of AD depends on
excluding conditions such as scabies, allergic
contact dermatitis, seborrheic dermatitis, cutaneous
lymphoma, ichthyoses, psoriasis, and other primary
disease entities.
Clinical Findings….
CHRONIC
Lichenification (rubbing)
Prurigo (picking)
ACUTE
Pruritus
Erythema
Infiltration or papulation
Vesiculation
Exudate
Treatment
• Restore hydration
• Identify and eliminate triggers
• Decrease pruritus and inflammation
Trigger Factors
• Irritants
• Allergens- some
controversy
• Infections- esp staph
Standard Therapies for Atopic Dermatitis
• Moisturization
• Irritant and allergen avoidance
• Topical corticosteroids
• Antibiotics
• Sedating antihistamines
• Phototherapy (PUVA, UVA, UVB, nbUVB)
• Immunosuppressive/Immunomodulatory
therapy. Cyclosporine 5mg/kg in severe cases
”But, Doc, sun light makes this better....."
I recommend narrow band UVB for some recalcitrant
cases of atopic dermatitis.
Topical Medications
• Age of patient
• Treatment site
• Extent/severity of disease
• Duration of treatment
• Potency desonide/hydrocortisone are non-florinated
• Triamcinolone is mid-potency, clobetasol is high-potency
• Formulation. Topical steroids can be very expensive
Topical Calcineurin Inhibiters
• Tacrolimus ointment .03% and .1%
• Pimecrolimus cream 1%
• Work by stopping up-regulation of
inflammatory lymphocytes
– No skin atrophy
– No telangiectasia
– No tachyphylaxis
– Black box warnings
Case study
Atopic Dermatitis with Secondary Impetiginization:Cleared with oral cephalexin, prednisone, and topical tacrolimus.
Case study
Eczema Herpeticum
9 month old boy with history of atopic dermatitis since 3 years old.
Developed widespread vesicular eruption aft er contact with family member with herpes labialis.
Treated with oral acyclovir, antihistamines, cool water compresses with dramatic improvement after one week.
This can be emergent. If child is “ill” (constitutional symptoms), consider hospital admission for IV acyclovir.
Ocular involvement is an EMERGENCY. (Consult ophtho immediately, but admit patient for IV acyclovir right away!)
Case study
Why is this child’s eczema so
recalcitrant to treatment?
Case study
Is it just a matter of
non-compliance?
Case study
Case study
Case study
Case study
Atopic Dermatitis Pearls
Moisturize, moisturize, moisturize…but do not put heavy emollients on before sweating as it can cause flares. Moisturize when the patient will be cool if possible.
Long-term continuous use of topical steroids can cause skin atrophy (striae).
Check zinc level in shild with recalcitrant well demarcated “eczema” on perioral area and in diaper area to rule out acrodermatitis enteropathica.
Remember to ask about recent exposure to family member with herpes labialis if atopic child has severe flare.
Ocular involvement in eczema herpeticum is an EMERGENCY. (Consult ophtho immediately, but admit patient for IV acyclovir right away!)
Use oil after bathing. Use moisturizing bar soap as the only soap and shampoo for atopic children.
Dosage Forms
INJ (pre-filled syringe): 300 mg per 2 mL
Adult Dosing
Atopic dermatitis, mod-severe
300 mg SC q2wk
Start: 600 mg SC divided in 2 sites x1
Dupixentdupilumab
Dupixentdupilumab
Safety/Monitoring
Monitoring Parameters
No routine tests recommended
Mechanism of Action
Binds to and inhibits interleukin-4 receptor alpha subunit, interfering with interleukin-4 and interleukin-13 cytokines, reducing inflammation and altering immune response (monoclonal antibody)
Dupixentdupilumab
Adverse Reactions
Serious Reactions
Hypersensitivity rxn
Serum sickness
Serum sickness-like rxn
Keratitis
Common Reactions
• Injection site rxn
• Conjunctivitis/Keratitis
• Blepharitis
• Herpes viral infection
• Ocular pruritus
• Dry eyes
References
ATOPIC DERMATITIS, Medscape, Ken Washenik, MD, PhD
Dermatlas
Medscape, Dermatology
MayoClinic.com
eMedicine